usr/src/usr.bin/split/split.c

/*
 * Copyright (c) 1987, 1993, 1994
 *      The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software developed by the University of
 *      California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#ifndef lint
static char copyright[] =
"@(#) Copyright (c) 1987, 1993, 1994\n\
        The Regents of the University of California.  All rights reserved.\n";
#endif /* not lint */

#ifndef lint
static char sccsid[] = "@(#)split.c     8.2 (Berkeley) 4/16/94";
#endif /* not lint */

#include <sys/param.h>

#include <ctype.h>
#include <err.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#define DEFLINE 1000                    /* Default num lines per file. */

long     bytecnt;                       /* Byte count to split on. */
long     numlines;                      /* Line count to split on. */
int      file_open;                     /* If a file open. */
int      ifd = -1, ofd = -1;            /* Input/output file descriptors. */
char     bfr[MAXBSIZE];                 /* I/O buffer. */
char     fname[MAXPATHLEN];             /* File name prefix. */

void newfile __P((void));
void split1 __P((void));
void split2 __P((void));
void usage __P((void));

int
main(argc, argv)
        int argc;
        char *argv[];
{
        int ch;
        char *ep, *p;

        while ((ch = getopt(argc, argv, "-0123456789b:l:")) != EOF)
                switch (ch) {
                case '0': case '1': case '2': case '3': case '4':
                case '5': case '6': case '7': case '8': case '9':
                        /*
                         * Undocumented kludge: split was originally designed
                         * to take a number after a dash.
                         */
                        if (numlines == 0) {
                                p = argv[optind - 1];
                                if (p[0] == '-' && p[1] == ch && !p[2])
                                        numlines = strtol(++p, &ep, 10);
                                else
                                        numlines =
                                            strtol(argv[optind] + 1, &ep, 10);
                                if (numlines <= 0 || *ep)
                                        errx(1,
                                            "%s: illegal line count.", optarg);
                        }
                        break;
                case '-':               /* Undocumented: historic stdin flag. */
                        if (ifd != -1)
                                usage();
                        ifd = 0;
                        break;
                case 'b':               /* Byte count. */
                        if ((bytecnt = strtol(optarg, &ep, 10)) <= 0 ||
                            *ep != '\0' && *ep != 'k' && *ep != 'm')
                                errx(1, "%s: illegal byte count.", optarg);
                        if (*ep == 'k')
                                bytecnt *= 1024;
                        else if (*ep == 'm')
                                bytecnt *= 1048576;
                        break;
                case 'l':               /* Line count. */
                        if (numlines != 0)
                                usage();
                        if ((numlines = strtol(optarg, &ep, 10)) <= 0 || *p)
                                errx(1, "%s: illegal line count.", optarg);
                        break;
                default:
                        usage();
                }
        argv += optind;
        argc -= optind;

        if (*argv != NULL)
                if (ifd == -1) {                /* Input file. */
                        if ((ifd = open(*argv, O_RDONLY, 0)) < 0)
                                err(1, "%s", *argv);
                        ++argv;
                }
        if (*argv != NULL)                      /* File name prefix. */
                (void)strcpy(fname, *argv++);
        if (*argv != NULL)
                usage();

        if (numlines == 0)
                numlines = DEFLINE;
        else if (bytecnt)
                usage();

        if (ifd == -1)                          /* Stdin by default. */
                ifd = 0;

        if (bytecnt) {
                split1();
                exit (0);
        }
        split2();
        exit(0);
}

/*
 * split1 --
 *      Split the input by bytes.
 */
void
split1()
{
        long bcnt;
        int dist, len;
        char *C;

        for (bcnt = 0;;)
                switch (len = read(ifd, bfr, MAXBSIZE)) {
                case 0:
                        exit(0);
                case -1:
                        err(1, "read");
                        /* NOTREACHED */
                default:
                        if (!file_open) {
                                newfile();
                                file_open = 1;
                        }
                        if (bcnt + len >= bytecnt) {
                                dist = bytecnt - bcnt;
                                if (write(ofd, bfr, dist) != dist)
                                        err(1, "write");
                                len -= dist;
                                for (C = bfr + dist; len >= bytecnt;
                                    len -= bytecnt, C += bytecnt) {
                                        newfile();
                                        if (write(ofd,
                                            C, (int)bytecnt) != bytecnt)
                                                err(1, "write");
                                }
                                if (len) {
                                        newfile();
                                        if (write(ofd, C, len) != len)
                                                err(1, "write");
                                } else
                                        file_open = 0;
                                bcnt = len;
                        } else {
                                bcnt += len;
                                if (write(ofd, bfr, len) != len)
                                        err(1, "write");
                        }
                }
}

/*
 * split2 --
 *      Split the input by lines.
 */
void
split2()
{
        long lcnt;
        int len, bcnt;
        char *Ce, *Cs;

        for (lcnt = 0;;)
                switch (len = read(ifd, bfr, MAXBSIZE)) {
                case 0:
                        exit(0);
                case -1:
                        err(1, "read");
                        /* NOTREACHED */
                default:
                        if (!file_open) {
                                newfile();
                                file_open = 1;
                        }
                        for (Cs = Ce = bfr; len--; Ce++)
                                if (*Ce == '\n' && ++lcnt == numlines) {
                                        bcnt = Ce - Cs + 1;
                                        if (write(ofd, Cs, bcnt) != bcnt)
                                                err(1, "write");
                                        lcnt = 0;
                                        Cs = Ce + 1;
                                        if (len)
                                                newfile();
                                        else
                                                file_open = 0;
                                }
                        if (Cs < Ce) {
                                bcnt = Ce - Cs;
                                if (write(ofd, Cs, bcnt) != bcnt)
                                        err(1, "write");
                        }
                }
}

/*
 * newfile --
 *      Open a new output file.
 */
void
newfile()
{
        static long fnum;
        static int defname;
        static char *fpnt;

        if (ofd == -1) {
                if (fname[0] == '\0') {
                        fname[0] = 'x';
                        fpnt = fname + 1;
                        defname = 1;
                } else {
                        fpnt = fname + strlen(fname);
                        defname = 0;
                }
                ofd = fileno(stdout);
        }
        /*
         * Hack to increase max files; original code wandered through
         * magic characters.  Maximum files is 3 * 26 * 26 == 2028
         */
#define MAXFILES        676
        if (fnum == MAXFILES) {
                if (!defname || fname[0] == 'z')
                        errx(1, "too many files.");
                ++fname[0];
                fnum = 0;
        }
        fpnt[0] = fnum / 26 + 'a';
        fpnt[1] = fnum % 26 + 'a';
        ++fnum;
        if (!freopen(fname, "w", stdout))
                err(1, "%s", fname);
}

void
usage()
{
        (void)fprintf(stderr,
"usage: split [-b byte_count] [-l line_count] [file [prefix]]\n");
        exit(1);
}